2018-09-04 18:36:43

by Colin King

[permalink] [raw]
Subject: [PATCH] Input: wm97xx: only unregister wm97xx_driver if it has been registered

From: Colin Ian King <[email protected]>

In the case where IS_BUILTIN(CONFIG_AC97_BUS)) is not true, the
wm97xx_driver driver is being unregistered even it has not been
previously registered. Fix this by only unregistering it if
IS_BUILTIN(CONFIG_AC97_BUS)) is true. This fixes the warning
message:

[ 834.111248] ------------[ cut here ]------------
[ 834.111248] Unexpected driver unregister!
[ 834.111319] WARNING: CPU: 2 PID: 11749 at drivers/base/driver.c:193 driver_unregister+0x3b/0x40
[ 834.111319] Modules linked in: wm97xx_ts(-) ....

..and a stack trace.

To easily reproduce this, load and unload the module on a system where
the hardware is not supported.

Fixes: ae9d1b5fbd7b ("Input: wm97xx: add new AC97 bus support")
Signed-off-by: Colin Ian King <[email protected]>
---
drivers/input/touchscreen/wm97xx-core.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/input/touchscreen/wm97xx-core.c b/drivers/input/touchscreen/wm97xx-core.c
index 2566b4d8b342..73856c2a8ac0 100644
--- a/drivers/input/touchscreen/wm97xx-core.c
+++ b/drivers/input/touchscreen/wm97xx-core.c
@@ -929,7 +929,8 @@ static int __init wm97xx_init(void)

static void __exit wm97xx_exit(void)
{
- driver_unregister(&wm97xx_driver);
+ if (IS_BUILTIN(CONFIG_AC97_BUS))
+ driver_unregister(&wm97xx_driver);
platform_driver_unregister(&wm97xx_mfd_driver);
}

--
2.17.1



2018-09-05 09:18:06

by Charles Keepax

[permalink] [raw]
Subject: Re: [PATCH] Input: wm97xx: only unregister wm97xx_driver if it has been registered

On Tue, Sep 04, 2018 at 07:35:05PM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> In the case where IS_BUILTIN(CONFIG_AC97_BUS)) is not true, the
> wm97xx_driver driver is being unregistered even it has not been
> previously registered. Fix this by only unregistering it if
> IS_BUILTIN(CONFIG_AC97_BUS)) is true. This fixes the warning
> message:
>
> [ 834.111248] ------------[ cut here ]------------
> [ 834.111248] Unexpected driver unregister!
> [ 834.111319] WARNING: CPU: 2 PID: 11749 at drivers/base/driver.c:193 driver_unregister+0x3b/0x40
> [ 834.111319] Modules linked in: wm97xx_ts(-) ....
>
> ..and a stack trace.
>
> To easily reproduce this, load and unload the module on a system where
> the hardware is not supported.
>
> Fixes: ae9d1b5fbd7b ("Input: wm97xx: add new AC97 bus support")
> Signed-off-by: Colin Ian King <[email protected]>
> ---

Acked-by: Charles Keepax <[email protected]>

Thanks,
Charles

2018-09-09 19:10:32

by Robert Jarzmik

[permalink] [raw]
Subject: Re: [PATCH] Input: wm97xx: only unregister wm97xx_driver if it has been registered

Charles Keepax <[email protected]> writes:

> On Tue, Sep 04, 2018 at 07:35:05PM +0100, Colin King wrote:
>> From: Colin Ian King <[email protected]>
>>
>> In the case where IS_BUILTIN(CONFIG_AC97_BUS)) is not true, the
>> wm97xx_driver driver is being unregistered even it has not been
>> previously registered. Fix this by only unregistering it if
>> IS_BUILTIN(CONFIG_AC97_BUS)) is true. This fixes the warning
>> message:
>>
>> [ 834.111248] ------------[ cut here ]------------
>> [ 834.111248] Unexpected driver unregister!
>> [ 834.111319] WARNING: CPU: 2 PID: 11749 at drivers/base/driver.c:193 driver_unregister+0x3b/0x40
>> [ 834.111319] Modules linked in: wm97xx_ts(-) ....
>>
>> ..and a stack trace.
>>
>> To easily reproduce this, load and unload the module on a system where
>> the hardware is not supported.
>>
>> Fixes: ae9d1b5fbd7b ("Input: wm97xx: add new AC97 bus support")
>> Signed-off-by: Colin Ian King <[email protected]>
>> ---
>
> Acked-by: Charles Keepax <[email protected]>
Acked-by: Robert Jarzmik <[email protected]>

Cheers.

--
Robert